The principle activity of the core will be the preparation of labeled and unlabeled icosanoids, analogues, standards, and inhibitors in sufficient amounts for biological testing, analytical services, and the development of RIAs. Generally all syntheses will be patterned on existing synthetic routes takes from the literature or developed in Dr. Falck's laboratory. Occasionally, it will be necessary to make modifications in the syntheses to accommodate the increased scale of the reactions. Appropriate analytical techniques, e.g., capillary GLC, HPLC and mass nmr spectroscopy, will be applied to intermediate and final products to verify identify and acceptable levels of purity. The core will be responsible for the storage, packing, and distribution of compounds to collaborating program laboratories. Since most icosanoids are available in only minute amounts from natural sources, the resources and services provided by the core facility are essential to the conduct of the program project. The metabolites of the epoxygenase pathway are considered good candidates for initial development of RIAs since they are novel icosanoids with potential relevance to renal function and because they lack a chromophore suitable for UV detection and quantification. RIA will be developed by standard methods utilizing rabbits. The RIAs will be validated by MS techniques.